Chevy Suburban electrical problems

I have a 2016 Chevy Suburban LT with rear seat entertainment system and approximately 30k miles. A few months ago, while our sons were watching a dvd while we were driving, I noticed that if I went to roll up two windows at the same time, it would reset the entertainment system (it would shut down for a second then come back on; also, the car’s headlights would dim for a split second). We didn’t think anything of this initially because it happened so rarely. However, it has started to happen very frequently, almost every time we take a trip. I’ve noticed that sometimes the voltmeter gauge bounces around–a little under 14 to a little over 14. A few days ago when we were driving on the highway, every time I pressed the brake, the headlights would flicker for a splitsecond again.

I then tested pressing the two window buttons, and sure enough my radio shut down for a second. I had it at the dealer and they say that they can’t replicate it, and they don’t know what could be causing it. I’m getting nervous to drive the vehicle based on this behavior. Any ideas? I’d be more than happy to answer any questions that you might have. Thank you kindly.

ANSWER: This sounds like a low voltage problem. Vehicle electronics do not like to have low system voltage. Each system is a little different as to what is considered low. Headlights will function just fine below 12 or 13 volts, but you will see a deference in brightness. More high tech electronics like computers, modules or other systems with circuit boards- like the entertainment system are much more sensitive.

The first thing you should have checked is the alternator. This is what keeps the battery charged and supplies the vehicle voltage. If a heavy load- such as several things running and pressing 2 window switches at the same time causes the voltage to drop, then the regulator inside the alternator may  not be functioning properly.

Your Suburban could also have a ground problem. A dirty or loose ground wire will also effect electrical circuits. There are many grounds on your truck- under the hood and inside the truck.

The best thing to do would to have as many accessories on with the truck running, then have the alternator load tested to see if it can keep up with the demand. If not, then a would suspect a bad alternator.